Breech bolt assemblies for firearms



Oct. 8 1968 .1. KOUCKY ETAL BREECH BOLT ASSEMBLIES FOR FIREARMS 2 Sheets-Sheet 1 Filed May 2-3, 1967 llllll llllll Q a F u on aw Q 9 mm Y s m V.. mK N C O Y. K 8 @w m mKm um fh A e n r mm a u E m 1968 .1. KOUCKY ETAL BREECH BOLT ASSEMBLIES FOR FIREARMS 2 Sheets-Sheet 2 Filed May 25, 196'? WW ON w M V- C OKU m W m N w o r I W um um A am .m mm

United States Patent 3,404,480 BREECH BOLT ASSEMBLIES FOR FIREARMS Josef Koucky and Frantisek Koucky, Prague, Czechoslovakia, assignors to Zavody Jana Svermy, narodni podnik, Brno, Czechoslovakia, a corporation Filed May 23, 1967, Ser. No. 640,668 Claims priority, application Czechoslovakia, May 24, 1966, 3,485/66 6 Claims. (CI. 4216) ABSTRACT OF THE DISCLOSURE A firearm provided with breech bolt assembly situated between the trigger and barrel of the firearm, the firearm being of the type which is adapted to receive a magazine. The firearm has within an outer housing thereof a breech bolt means provided at its rear portion with a head, and this head has an upper portion and a pair of opposed side portions. At its upper portion, the head is formed with a longitudinal groove receiving an elongated striker in the form of a one-piece body of sheet metal, while beneath the striker the head is formed with an opening which receives a manually operable cocking means in the form of an elongated cylindrical member having an outer handle and in the region of the latter handle a retaining flange is provided which engages an inner surface of the outer housing which accommodates the breech bolt. The cylindrical member of the cocking means extends through a slot in the outer housing and at its end which is distant from its handle is provided with a notch which receives an ejector means carried by the other of the opposed sides of the head of the breech bolt. The head of the breech bolt carries at its side which is opposed to the ejector means an extractor means which is swingably supported by the head.

Background of the invention The present invention relates to firearms.

In particular, the present invention relates to firearms in the form of automatic rifles or the like used for hunting and other sporting purposes.

In particular, the present invention relates to breech bolt assemblies of such firearms, these breech bolts being of the shiftable type.

The shiftable breech bolts which are presently known are arranged so that the elongated larger part of their mass extends forwardly beneath the rear part of the barrel of the firearm where only a cocking handle is located. Most of the operative elements are situated in a relatively short rear part of the breech bolt, the so-called breech bolt head, and because of the limited space which is available at the breech bolt head considerable difliculties are encountered in properly situating the relatively large number of important operative components. Not only is there a difliculty encountered in arranging all the parts, but in addition difiiculty is encountered in manufacturing the breech bolt itself which is not only complex but also is difficult to disassemble and reassemble with the other components.

Summary of the invention It is therefore a primary object of the present invention to provide a firearm structure which will avoid all the above drawbacks.

In particular, it is an object of the present invention to provide a firearm structure with a breech bolt assembly wherein all of the components can be accommodated without difiiculty While operating properly.

Furthermore, it is an object of the present invention to provide a construction which can be easily disassembled and reassembled.

3,404,480 Patented Oct. 8, 1968 In particular, with the firearm of the invention the breech bolt means has a head provided with an upper portion and a pair of side portions, and an elongated striker means is situated in a groove of the upper portion of the head for longitudinal movement therealong, this striker means being in the form of a fiat member made of a single body of sheet metal, for example, and resiliently mounted with a push or snug fit in the grove at the upper portion of the head. At one of the side portions of the head is an extractor means which is supported for swinging movement, and this extractor means has an extractor housing provided with a bore in which is situated a spring which presses on a pin which engages a surface of a recess in which the extractor means is accommodated, this recess being formed in the head of the breech bolt means, beneath the striker means the head of the breech bolt means is formed with an opening which receives a manually operable cocking means. This manually operable cocking means is in the form of an elongated cylindrical member provided with an exterior handle, and in the region of the latter handle with a retaining flange which slidably engages an inner surface of an outer housing in which the breech bolt means is accommodated, this cylindrical member of the cocking means extending through an elongated slot which is formed in the outer housing of the firearm. The retaining flange forms an extension of a pair of opposed parallel flats which enable the cylindrical member of the cocking means to be introduced through the slot of the outer housing into the opening of the breech bolt means, and this cylindrical member has a shank formed with recesses displaced by with respect to the pair of parallel flats and adapted to accommodate portions of a magazine which is carried by the firearm. At its ends which is opposite to its handle the elongated cylindrical member of the cocking means is formed with a slot or notch which receives an ejector means which is carried by the other of the opposed sides of the head of the breech bolt means. At its rear end the slot of the outer firearm housing which receives the breech bolt means has an enlarged portion through which the cylindrical member of the cocking means may initially extend, enlarged rear portion of the slot being large enough to enable the retaining flange to pass therethrough so that this retaining flange can then be situated forwardly of the rear end portion of the slot to slidably engage an inner surface of the outer housing of the firearm.

The advantages of the structure of the invention reside in the simplicity of the manufacture thereof. Thus, the structure for guiding the striker and the striker itself are exceedingly simple, in that the guide structure is a simple slot and the striker itself need only be made of a part of a sheet metal body. The striker makes it possible to form a solid extractor means having a pin which can easily be accommodated quite close to the longitudinal axis of the breech bolt means. Thus it becomes possible to situate the extractor means at a location isolated from the remaining components so that there will be no difficulties in connection with the operation of the remaining components even when a cartridge is extracted with dithculty by the extracting means. Furthermore, the arrangement of the breech bolt means of the invention enables the active spring of the extractor means to be situated in the interior of the extractor housing and not within the breech bolt structure itself. The cocking means in the form of an elongated cylindrical handle is of an exceedingly convenient and simple construction due primarily to its substantially cylindrical configuration which is simple to manufacture.

It is a simple matter to shift this cylindrical member of the cocking means into a suitably formed opening provided in the head of the breech bolt means.

A Brief description of the drawings The' invention is illustrated by way of example in the accompanying drawings which form part of this application and in which:

FIG. 1 is a schematic fragmentary side view of a firearm according to the invention showing the receiver and trigger mechanism in a disassembled condition;

FIG. 2 is a transverse fragmentary section taken along line 22 of FIG. and showing details of the structure of the invention;

FIG. 3 is a perspective illustration of the manually operable cocking means of the invention;

FIG. 4 is a partly sectional longitudinal side elevation fragmentarily illustrating the breech bolt means of the invention and part of the components accommodated thereby; and

FIG. 5 is a partly sectional top plan view of the breech bolt means showing how it appears with part of the outer housing of the rifle removed so as to more clearly illustrate the details of the structure of the invention.

Description of a preferred embodiment Referring now to the drawings there is shown, in FIG. 1, for example, an elongated breech bolt means 2 which extends at its forward end beneath the rear end of the barrel, as indicated. At its rear portion the breech bolt means 2 is provided with a head 1 which is provided with an upper portion and a pair of opposed side portions. The upper portion of the head 1 is formed with an elongated groove 3 (FIG. 5) extending longitudinally of the head 1 and receiving in its interior an elongated striker 5 in the form of a one-piece body which may be cut from a suitable sheet metal. The elongated striker 5 has a push or snug sliding fit within the groove 3, and between its ends the striker 5 is formed with an opening through which a pin 4 extends; this pin 4 being carried by the head 1 of the breech bolt means 2. The striker 5 is spring loaded by a spring 6 (FIG. 4) received in a suitable recess of the head 1 and acting on a rear extension of the striker 5 so as to urge the latter rearwardly. At its front end the striker 5 carries the firing pin 7.

At one of its side portions, the head 1 of the breech bolt means 2 carries an extractor means 9 which is supported for swinging movement by the head 1 of the breech bolt means 2. This extractor means 9 is supported for swinging movement on a pin 8 which is carried by the head 1. The extractor means 9 has an outer extractor housing formed with a bore which is open at its rear end and which accommodates in its interior a compressed coil spring 10 which acts on a shoulder of a pin 12. Thus, the rear end of the pin 12 extends outwardly beyond the rear open end of the bore 11 in which the spring 10 is situated together with the forward portion of the pin 12. The extractor means 9 is accommodated within a recess 14 which is formed in the left side portion of the head 1, as viewed in FIG. 2, although the details of the extractor means are most clearly apparent from FIG. 5. This recess 14 has at its rear a forwardly directed surface 13 (FIG. 5), and it is against this surface 13 that the rear end of the pin 12 is pressed by the spring 10 so that the extractor means 9 is urged to swing in a counterclockwise direction about the pin 8, as viewed in FIG. 5.

Beneath the striker means 5 the head 1 of the breech bolt means 2 is formed with a transverse opening 15 (FIG. 2), and this opening or bore 15 extends into the head 1 from the left side thereof, as viewed in FIG. 2, this opening or bore 15 extending across the recess 16 of the head which accommodates the magazine 17 as indicated in FIG. 2. This bore or opening 15 extends to the region where the ejector means 18 is situated, as is also apparent from the FIG. 2.

The bore or Opening 15 of the head 1 accommodates a manually operable cocking means 22 in the form of an elongated cylindrical member which is shown by itself in FIG. 3. This cocking means 22 has an exterior handle 19 and in the region of the latter a retaining flange 20 provided with a pair of opposed parallel flats 21. The cylindrical or substantially cylindrical cocking means 22 is provided at the side of the retaining flange 20 opposite from the handle 19 with recesses 23 for accommodating the magazine 17 where the cocking means 22 extends across the recess 16 which receives the magazine 17, and in order that the cocking means 22 may be introduced in either one of a pair of angular positions which are displaced 180 with respect to each other, a pair of recesses 23a are provided at the upper and at the lower sides of the cylindrical member, as indicated in FIG. 3, these recesses being displaced by with respect to the pair of parallel flats 21. At its end which is opposed to the handle 19, the shank of the cocking means 22 is formed with an axially extending notch 24 which receives the ejector means 18, as is apparent from FIG. 2.

The head 1 of the breech bolt means 2 is accommodated within an outer housing 28 of the firearm, and at its left wall, as viewed in FIG. 2, this outer housing 28 is formed with an elongated slot through which the cocking means 22 can be introduced in the opening 15 of the head 1. Once it is situated in the opening 15, the cocking means 22 has its retaining flange 20 in slidable engagement with the edge portions 25 and 26 which define the narrow slot portion 27 formed in the side of the outer housing 28 of the firearm. This outer housing 28 forms the receiver of the firearm, as is apparent from FIG. 1. At its rear end the slot 27 has a downwardly extending enlarged portion 29 large enough to accommodate the entire retaining flange 20, so that at the enlarged rear portion 29 it is possible to introduce the retaining flange 20 through the slot so that the retaining flange 20 can then engage the inner side surface of the housing or receiver 28 at the region of the slot 27.

The cocking means 22 is displaced, by manual engagement of the handle portion 19 thereof, so as to move during a part of its cycle of movement in the ejecting hole 30 which forms an extension of the slot 27 in the side of the receiver 28, and during the remaining part of this movement the cocking means moves along the slot portion 27.

When the firearm arm is disassembled, as indicated in FIG. 1, the manually operable cocking means 22 is removed through the enlarged rear portion 29 of the slot 27, and then the breech bolt means 2 can be disassembled so as to be separated from the remainder of the components of the firearm. Thus, the trigger mechanism 31 indicated in FIG. 1 can be removed from the receiver 28. Inasmuch as the breech bolt means 2 will this time no longer be held by the trigger mechanism from beneath the breech bolt means 2, this breech bolt means can be tilted so that the retaining flange 20 will no longer remain in engagement with the edges 25 and 26 of the slot 27 and instead can be displaced rearwardly to the enlarged rear portion 29 which is large enough to enable the retaining flange 20 to pass through the wall of the receiver of housing 28, thus enabling the structure to be disassembled. In this way, the cocking means 22 can be removed from the opening 15. The parts are reassembled through the reverse of this procedure.

What is claimed is:

1. In a firearm, breech bolt means having a head provided with an upper portion and a pair of opposed side portions, elongated striker means carried by said breech bolt means at said upper portion of said head thereof for longitudinal movement therealong, extractor means swingably carried by said head of said breech bolt means at one of said pair of opposed side portions thereof, manually operable cocking means carried by said head and extending into said head in a direction transverse to the movement of said striker means, said head being formed with an opening which receives said cocking means, and ejector means carried by the other of said side portions of said head.

2. The combination of claim 1 and wherein said upper portion of said head is formed with a longitudinal groove which receives said striker means, said striker means being in the form of an elongated one-piece member received in and slidable along said groove.

3. The combination of claim 1 and wherein said extractor means includes an outer extractor housing swingably carried by said One side portion of said head, said housing being formed with a bore, a spring situated in said bore, and a pin acted upon by said spring to be urged by the latter out of said housing of said extractor means said spring and pin also forming part of said extractor means and said head being formed with a recess accommodating said housing of said extractor means and defined in part by a surface of said head against which said pin is pressed bysaid spring. a a r 4 4. The combination of claim 1 and wherein said manually operable cocking means is in the form of an elongated cylindrical member having an exterior handle adapted to be engaged by the operator and provided in the region of said handle with a retaining flange, said firearm including an outer housing accommodating said breech bolt means and formed at one side with a slot through which said cylindrical member of said cocking means extends, said retaining flange slidably engaging an inner surface of said outer housing at opposed sides of said slot thereof, and said elongated cylindrical member being formed in the plane of said retaining flange with a pair of opposed flats which are parallel to each other to facilitate introduction of said cocking means into and out of said opening of said breech bolt means through said slot of said outer housing, said elongated cylindrical member being formed on the opposite side of said retaining flange thereof from said handle with recesses for accommodating portions of a magazine and said cylindrical member terminating at its end opposite from said handle in a notch which receives said ejector means at the other of said side portions of said head.

5. The combination of claim 4 and wherein said recesses of said cylindrical member of said cocking means are displaced by with respect to said parallel flats.

6. The combination of claim 5 and wherein said slot in said outer housing is formed at its rear end with an enlargement through which said retaining flange can pass so that when initially introducing said cocking means into said opening of said head of said breech bolt means said retainingfiange can pass, through said enlarged rear end of said slot of said outer housing before advancing forwardly along the latter slot to slidably engage an inner surface of said outer housing.

References Cited UNITED STATES PATENTS 950,576 3/l910 Paulson 4216 1,317,587 9/1919 Mercie 4216 1,423,836 7/1922 Declaye 4269 2,659,994 11/1953 Yale 4269 2,741,950 4/1956 Smith 4269 3,203,129 8/1965 Elkas 4269 BENJAMIN A. BORCHELT, Primary Examiner. 

